Pennsylvania's Senate Race: The Very Definition of Tossup

York, Pennsylvania - Pennsylvania has a reputation as a political swing state, but even the savviest students of politics are scratching their heads in confusion over which way the U.S. Senate race between Democrat Joe Sestak and Republican Pat Toomey will swing on Tuesday.

Looking at polls in this race is like watching a boxing scene from "Rocky": Toomey's well up in one round, Sestak's slightly ahead in another, then they're tied the next.

"Sestak has created an image of a comeback guy," and polls show both candidates under 50 percent, "so no one has closed the sale," said Lee Miringoff, the director of Marist College's Institute for Public Opinion, which polls the state. "And Democrats are really trying hard right now to wake up their sleepy base."

Few count Sestak out, especially Toomey.

"It's going to be competitive down to the end," Toomey predicted earlier this week in West Chester, Pa.

"They tried to put me on the mat earlier this summer — spent millions of dollars in ads — but I'm not on the mat," Sestak said of efforts by Toomey, the GOP campaign committees and outside interest groups.

With Election Day fast approaching and the number of undecided voters in the Keystone State rapidly dwindling, both candidates are looking to deliver a knockout blow and have enlisted some of the biggest names in their parties to help.

Sestak, a two-term congressman and retired Navy three-star admiral, campaigned side by side with former President Bill Clinton Thursday at rallies in the Philadelphia area and a black college in Cheney, Pa. That's largely an effort to light a fire under a Democratic base that polls show less motivated to vote Tuesday than Republicans are.

President Barack Obama will return to Philadelphia Saturday for the second time this month to help launch canvassing for Democratic candidates, including Sestak. First lady Michelle Obama will follow her husband's Philadelphia campaign visit with one of her own on Monday.

Not to be outdone, Toomey, a former three-term congressman and the former head of the Club for Growth — an advocacy group for low taxes, fiscal discipline and free trade — is bringing in some heavyweights of his own.

Rising GOP star Chris Christie, the governor of neighboring New Jersey, and Govs. Tim Pawlenty of Minnesota and Haley Barbour of Mississippi, both potential 2012 presidential candidates, are scheduled to campaign with Toomey in Lancaster, Pa.

G. Terry Madonna, the director of the Center for Politics & Public Affairs at Franklin & Marshall College in Lancaster, Pa. and a veteran analyst of state politics, thinks a Sestak victory is a long shot, but adds that the Clinton-Obama appearances could boost Democratic turnout in a state where registered Democrats outnumber registered Republicans 4.3 million to 3.1 million.

"All of the turnout efforts, from what we see now, with Clinton and the Obamas, could pay off in the southeast (portion of the state)," Madonna said. "Christie will marginally help Toomey because he's close to Pennsylvania. Barbour and Pawlenty don't have the star power of Clinton or Obama."

For Sestak to succeed, he must reprise his role as the "Comeback Kid." He wasn't even supposed to be in this race: Democratic Party leaders tried to pressure him to stand down from a Senate run to clear a path for Arlen Specter, Pennsylvania's five-term Republican senator who switched parties in 2009 after concluding that he couldn't defeat Toomey in a GOP primary.

Sestak bucked his party leaders, ran against Specter in a Democratic primary and scored an unexpected come-from-behind victory in May over the better-financed, better-connected Specter.

Since then, Sestak and Toomey have been going at each other hard on the campaign trail, each portraying the other as extreme.

Toomey tags Sestak as the third wheel of a liberal triumvirate headed by House Speaker Nancy Pelosi, D-Calif., and Senate Majority Leader Harry Reid, D-Nev., because of his "yes" votes on health care, Obama's economic stimulus package, and the bank bailout.

"The examples are endless, and consistently Joe comes down on an extreme set of policy proposals to the left of Nancy Pelosi and way outside of the consensus of even the Democratic Party," Toomey said at a Rotary Club luncheon in York.

Sestak responds by lumping Toomey into his version of a political Axis of Evil along with tea party favorites Sarah Palin and Delaware Republican Senate candidate Christine O'Donnell. Toomey isn't a tea party candidate, but Palin has endorsed him.

Sestak repeatedly reminds voters of Toomey's Club for Growth tenure, his post-congressional ties to Wall Street firms, and support for lowering the business tax rate to 25 percent from 35 percent.

"I tell everybody that he (Toomey) isn't a witch, but his policies are scary," Sestak said in Philadelphia, an allusion to O'Donnell's long-ago flirtation with witchcraft.

O'Donnell has become a weapon of choice for Sestak and Pennsylvania Democrats, who theorize that her ads, which air in greater Philadelphia's media market to reach Delaware, arouse voters in the Keystone state alarmed by the tea party. Sestak thinks that linking Toomey to O'Donnell and Palin "gives voters pause" and makes them wonder whether they'll have "buyer's remorse" if they vote for Toomey.

Some analysts dismiss that theory.

"It would be a stretch that Democrats in Pennsylvania would get a boost because of her ads," said Jason Mycoff, a University of Delaware political science professor. "I understand where Democrats are coming from with this, but I think it's wishful thinking."

Sestak also hasn't neglected the Democratic tradition of blaming former President George W. Bush for the sour economy. He recently launched a TV ad in equating cleaning up the economy after Toomey and Bush to cleaning up after the Sestak family dog.

"My family loves Belle, but she can make a mess," Sestak says in the ad, which features him dumping a bag of Belle's business in the trash. "It made me sick to bail out the banks, but I had to clean up the mess left by these guys."

Toomey said Sestak's moves smack of desperation.

"I've been out of Congress for six years. Joe's been there for the last four years, voting for all the bailouts, the stimulus, all the spending, voting for all these huge deficits and debt, and he wants to try to blame me for his votes," Toomey said in York. "Joe ought to take responsibility for the damage Joe is doing, and this ad is another way to try to avoid that responsibility."